Prochaska and DiClemente's Transtheoretical Model has focused on identifying the processes of change that appear to underlie the modification of addictive behaviors, providing a way of conceptualizing and measuring clients' readiness to change their alcohol use. The proposed study will examine the relationship between dimensions of psychiatric severity and several change measures for alcoholism treatment from the Transtheoretical Model. It will also compare these change "mechanisms" of alcohol abusing or dependent patients with high levels of psychiatric severity to those of alcohol abusing/dependent patients with low levels of psychiatric severity. Specifically, the project will: 1) Determine the relationship between psychiatric severity and the Transtheoretical Model constructs of stages and processes of change for alcohol use, alcohol decisional balance, and alcohol abstinence self- efficacy in a sample of 150 alcohol dependent patients in a Dual Diagnosis treatment program. 2) Determine if and how these dually diagnosed subjects' stage of change profiles, readiness to change, processes by stage interactions, decisional balance, and self-efficacy differ from those of a sample of subjects in an alcoholism treatment program who have comparable levels of alcohol abuse or dependence, but low scores on a measure of psychiatric severity. There will be two components to this study. In the first component, 150 patients from a residential dual diagnosis treatment program, who are dually diagnosed with alcohol abuse or dependence and a concurrent psychiatric problem, will be measured on psychiatric severity and on the Transtheoretical Model constructs of Stage of Change, Processes of Change, Alcohol Decisional Balance, and Alcohol Abstinence Self-Efficacy. The purpose of this component of the study will be to determine the relationships between psychiatric severity and the Transtheoretical constructs. In the second component, a sample of subjects from the Dual Diagnosis sample with high psychiatric severity scores will be compared with a matched sample of Project MATCH subjects who scored low on psychiatric severity. Comparisons between the two groups will be made on each of the four Transtheoretical Model constructs to determine whether the two groups differ in the way they approach behavior change.